San Diego’s city's hurry-up environmental process for a new Chargers stadium in Mission Valley now looks certain to draw legal opposition that could delay the project beyond NFL timelines.

A Hermosa Beach law firm has just filed a preliminary document -- in response to a call for public comments to the city’s draft report – that figures to be an obvious forerunner to formal litigation once the EIR is certified. Click here to read the full document.

City officials aren’t impressed with the issues it raises.

But the Chargers and leading team backers see it as a real threat to keeping the Bolts local.

"These folks have already start to dissect the environmental and legal issues,” said San Diego attorney Cory Briggs. “Even at this early stage, they've got 135 pages of legal defects. It's only going to get worse because when you rush something of this magnitude, you exponentially increase the likelihood of mistakes."

While Briggs isn't involved with the filing by attorneys from Chatten-Brown & Carstens LLP, he echoes the concerns raised by that firm, which also represents environmental activist groups throughout the state.

"Truth is stranger than fiction,” Briggs said in an interview Tuesday. "Here it's turned out that what the city is doing is worse than anybody could have imagined."

That's a major concern for the San Diego Stadium Coalition, a 20,000 member group working to keep the Chargers in town -- either in Mission Valley, or downtown's East Village, where the team has been holding out for a hybrid stadium-convention facility.

But that idea is opposed by downtown hoteliers who fear losing room tax proceeds to a scheme that would go toward funding a stadium project there.

"When you look at that giant document, all the things they laid out, these are common concerns, commonly addressed in the EIR process,” said Jason Riggs, the stadium coalition’s founder. “But unfortunately the timeline's so compressed that there's no way you can address all of those."

Given a worst-case scenario in which the city’s EIR winds up in court, with the stadium project delayed for who-knows-how-long, Riggs told NBC 7 that the city may need to pivot toward East Village.

"The big caveat is the mayor has to get the hoteliers on board,” Riggs said. “The Chargers aren't going to spend a bunch of money on a citizens initiative if they have to go and fight the mayor and hoteliers while trying to promote this thing to the voters.

“If the mayor would just open up downtown -- he's said he may be open to it -- I think that would really eliminate all of these issues that we're seeing,” Riggs continued. "And the team would actually, I think, get back to the table and start negotiating -- which is what we all want … if it does happen we think a citizens' initiative could be put together and on the ballot by next November."

No comment was forthcoming from Mayor Kevin Faulconer’s office, but the upshot of a response from the city was that the challenge is based on unfounded assumptions and arguments that'll get tossed out of court.

This written statement was offered by Councilman Scott Sherman, whose district includes the stadium site: "Petco Park was sued 18 times, but was successful at every turn. If we halt progress just because of lawsuits, nothing will ever get accomplished."